1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Copyright (C) 2017, STMicroelectronics - All Rights Reserved 4 * Author(s): Patrice Chotard, <patrice.chotard@st.com> for STMicroelectronics. 5 */ 6 7 #include <common.h> 8 #include <dm.h> 9 #include <errno.h> 10 #include <reset-uclass.h> 11 #include <stm32_rcc.h> 12 #include <asm/io.h> 13 14 /* reset clear offset for STM32MP RCC */ 15 #define RCC_CL 0x4 16 17 struct stm32_reset_priv { 18 fdt_addr_t base; 19 }; 20 21 static int stm32_reset_request(struct reset_ctl *reset_ctl) 22 { 23 return 0; 24 } 25 26 static int stm32_reset_free(struct reset_ctl *reset_ctl) 27 { 28 return 0; 29 } 30 31 static int stm32_reset_assert(struct reset_ctl *reset_ctl) 32 { 33 struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev); 34 int bank = (reset_ctl->id / BITS_PER_LONG) * 4; 35 int offset = reset_ctl->id % BITS_PER_LONG; 36 debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__, 37 reset_ctl->id, bank, offset); 38 39 if (dev_get_driver_data(reset_ctl->dev) == STM32MP1) 40 /* reset assert is done in rcc set register */ 41 writel(BIT(offset), priv->base + bank); 42 else 43 setbits_le32(priv->base + bank, BIT(offset)); 44 45 return 0; 46 } 47 48 static int stm32_reset_deassert(struct reset_ctl *reset_ctl) 49 { 50 struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev); 51 int bank = (reset_ctl->id / BITS_PER_LONG) * 4; 52 int offset = reset_ctl->id % BITS_PER_LONG; 53 debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__, 54 reset_ctl->id, bank, offset); 55 56 if (dev_get_driver_data(reset_ctl->dev) == STM32MP1) 57 /* reset deassert is done in rcc clr register */ 58 writel(BIT(offset), priv->base + bank + RCC_CL); 59 else 60 clrbits_le32(priv->base + bank, BIT(offset)); 61 62 return 0; 63 } 64 65 static const struct reset_ops stm32_reset_ops = { 66 .request = stm32_reset_request, 67 .free = stm32_reset_free, 68 .rst_assert = stm32_reset_assert, 69 .rst_deassert = stm32_reset_deassert, 70 }; 71 72 static int stm32_reset_probe(struct udevice *dev) 73 { 74 struct stm32_reset_priv *priv = dev_get_priv(dev); 75 76 priv->base = dev_read_addr(dev); 77 if (priv->base == FDT_ADDR_T_NONE) { 78 /* for MFD, get address of parent */ 79 priv->base = dev_read_addr(dev->parent); 80 if (priv->base == FDT_ADDR_T_NONE) 81 return -EINVAL; 82 } 83 84 return 0; 85 } 86 87 U_BOOT_DRIVER(stm32_rcc_reset) = { 88 .name = "stm32_rcc_reset", 89 .id = UCLASS_RESET, 90 .probe = stm32_reset_probe, 91 .priv_auto_alloc_size = sizeof(struct stm32_reset_priv), 92 .ops = &stm32_reset_ops, 93 }; 94